#470 fix(cli): emit compact tune JSON

[Anonymous]

Originally created by: slegarraga

Closes [#431]

What

• Adds separators=(",", ":") to the tune --json serialization.
• Keeps sorted keys, default string conversion, fields, and schema unchanged.

Tests

• Adds tests/unit/test_cli_tune_json.py, shaped like the scan JSON test: seeds decisions through storage, parses the CLI output, and asserts neither spaced JSON separator appears.

Verification

• .venv/bin/pytest tests/unit/test_cli_tune_json.py — 1 passed.
• .venv/bin/pytest tests/unit/test_friction_tune.py tests/unit/test_cli_tune_json.py — 24 passed.
• Full local suite: 3,180 passed, 12 skipped; one unrelated integration plugin-discovery test also fails on clean main in this environment because its isolated Python cannot import doberman.
• .venv/bin/ruff check and .venv/bin/ruff format --check pass on changed files.

[Anonymous]

Ticket changed by: fu351

• status: open --> closed

[Anonymous]

Ticket changed by: fu351

• status: closed --> open

[Anonymous]

Ticket changed by: fu351

• status: open --> closed

[Anonymous]

Ticket changed by: fu351

• status: closed --> open

[Anonymous]

Ticket changed by: fu351

• status: open --> closed

[Anonymous]

Originally posted by: fu351

Merged, thanks @slegarraga! Asserting that neither spaced separator appears in the raw output is the test I wanted here, it fails the moment anyone drops separators= again.